VACalculator is a scientific calculator written in JavaScript with a large number of built-in functions. It is optimized for Onyx M92 but it should work in any modern browser.

You can define your own variables for later use. Simple 2D plots are possible in the current window. To be able to access the help file while running the calculator, please put the files "vacalculator.htm" and "vacalculator-doc.htm" in the same folder.

The usage is very simple: just press the buttons to construct the expression in the input box and then hit [Compute]; the result appears in the same box.